In the Skanda Purāṇa there is a statement eulogizing the tulasī tree as follows: “Let me offer my respectful obeisances unto the tulasī tree, which can immediately vanquish volumes of sinful activities. Simply by seeing or touching this tree one can become relieved from all distresses and diseases. Simply by offering obeisances to and pouring water on the tulasī tree, one can become freed from the fear of being sent to the court of Yamarāj [the King of death, who punishes the sinful]. If someone sows a tulasī tree somewhere, certainly he becomes devoted to Lord Kṛṣṇa. And when the tulasī leaves are offered in devotion at the lotus feet of Kṛṣṇa, there is the full development of love of Godhead.”
In India every Hindu, even those not belonging to the Vaiṣṇava group, take special care of the tulasī tree. Even in great cities where it is very difficult to keep a tulasī tree, people are to be found very carefully keeping this plant. They water it and offer obeisances to it, because worship of the tulasī tree is very important in devotional service.
In the Skanda Purāṇa there is another statement about tulasī, as follows: “Tulasī is auspicious in all respects. Simply by seeing, simply by touching, simply by remembering, simply by praying to, simply by bowing before, simply by hearing about or simply by sowing this tree, there is always auspiciousness. Anyone who comes in touch with the tulasī tree in the above-mentioned ways lives eternally in the Vaikuṇṭha world.”
The Nectar of Devotion – Chapter 11
His Divine Grace A.C. Bhaktivedanta Swami Prabhupāda

The Nectar of Devotion, written by Srila Rupa Goswami, is a detailed exposition on the path of pure devotional service to the Supreme Personality of Godhead, Krishna.